Here in Ontario, we have a similar legislation to the Section 508 called
ODA, Ontarians with Disabilities Act (2001) which is based on WAI-AA level.
The ministries of the government all produce publications and through a tool
called LIO (pronounced, "Leo"), anyone can to a geospatial search for
publications. The LIO tool is Java-based and therefore very difficult to
make accessible much like any of the map sites such as MapQuest might be.
Another tool we have is called CLAIMaps which is a Java-based, geospatial
tool for searching for mining claims - again, very difficult to make
accessible. ODA has an exemption clause which simply states that if it is
not technically feasible to make a sub-web ODA-compliant, it may be
exempted. For these sub-webs, this is what has been applied to them.